This invention relates generally to systems for forming discrete groups of articles so that these article groups can be dropped into upwardly open packing cases, and deals more particularly with a grouper of the pin type having upstanding pins for entry between adjacent articles in a line of articles. Predetermined numbers of articles are first decelerated and then accelerated to form a space therebetween in order to provide for positive handling of groups of the articles by a pocket chain conveyor or constant velocity conveyor equipped with upstanding lugs spaced apart at predetermined distances to accommodate the article groups therebetween.
The conveyor system for forming discrete groups of article to be described herein is especially adapted for use with a continuous motion bottle packer of the type shown in a pending application entitled "Continuous Motion Bottle Packer", Ser. No. 425,104 filed Sept. 27, 1982 and assigned to the assignee herein. This pending application shows a plurality of grids provided in a rotary structure which is adapted to move each grid in turn through an infeed station where the groups of article are fed into the grid without interrupting their forward speed. Each grid is in turn moved through a discharge station where the groups of articles are dropped into upwardly open packing cases. Both the infeed and discharge station operate without interrupting the motion of the articles or the movement of the packing case itself. The disclosure in said pending application is incorporated by reference herein. A brief description of the overall packer follows.
The continuous motion bottle packer as disclosed in the pending application includes article conveyor means for advancing the bottles continuously in side-by-side columns along a first horizontal path. These articles are arranged in end-to-end relationship betwen lane dividers, and means is provided for forming groups of these articles corresponding to the capacity of the cases to be packed. The means for grouping the articles, are provided in the packer, comprises a pin conveyor operated at a slightly slower speed than an underlying article lane conveyor to allow predetermined numbers of articles to advance in orderly groups toward the infeed station of the packer. Indexing means is provided at the downstream end of the lane conveyor to assure that the article groups move in timed relationship into the orbiting grid structures which carry the groups of articles around a circular path to a discharge station where they are deposited into upwardly open packing cases, all without interruption of the speed of movement both of the articles and of the packing cases.
The infeed station at the downstream end of these lane conveyors includes fixed cantilever mounted fingers for slidably receiving columns or lanes of articles, and these fingers are spaced to define horizontally extending openings therebetween. The grid structures are designed to pass upwardly through these finger openings as a result of the unique construction of each grid. Each grid consists of longitudinally extending support rails which carry corner posts defining pockets for the individual articles. Front and rear cross members of each grid structure are provided for supporting the ends of these rails, and the corner post have upper portions which fit between adjacent articles in the advancing article group as each grid moves upwardly through the infeed station.
The grid structures move in a circular orbit oriented in a vertical plane and the tangential direction of movement for the grid structures entering the infeed station forms an acute angle with the horizontal path of the articles themselves arriving at the infeed station. The horizontal component of velocity for the grid structures at the infeed station is such that it matches the horizontal speed of the articles moving into the infeed station under the control of the indexing means. This provides for a slight acceleration of the grid and the articles entrained therein as the grid moves away from the infeed station. The tangential speed of the grid exceeds the speed of the articles moving into the infeed station.
Thus, the articles move at a controlled speed through the infeed station into each grid structure where they are transported around approximately 180 degrees of circular travel to a discharge station. Each grid structure includes pivoted vanes for engaging and supporting the underside of the articles and these vanes receive each article in the group so as to carry the article away from the infeed station without interrupting their forward motion. A smooth transition for the motion of the articles is achieved from a straight infeed line to the circular orbit and the article groups are themselves pivotally carried in the rotating grid support structure so they remain in horizontal orientation as they travel to the discharge station.
The discharge station is defined at the low point of the orbit, and a case conveyor moves upwardly open cases continuously through the discharge station, being driven at a speed which varies cyclically to correspond to the horizontal component of motion for each orbiting grid structure as it moves through the discharge station. Slightly ahead of the low point in the orbit, the pivoted vanes supporting the articles are retracted beneath the grid rails and the articles are allowed to free fall into the upwardly open packing case moving immediately below the grid structure. A funnel structure is provided in each grid structure for guiding the articles into the packing case or more particularly into individual pockets defined by the packing case and also serves to decelerate the articles as they are dropped in guided fashion, again without interrupting the motion for the articles and of the continuously moving packing case.
The chief aim of the present invention is to provide an article grouper for a continuous motion bottle packer of the type described above so as to achieve a smooth grouping of the bottles prior to moving them in controlled fashion to the infeed station. The groups are accelerated away from the grouper by flat chain conveyors associated with each of several article lanes, and by conveyors moving the groups off these chain conveyors into the infeed station.